Hi stahrgeyzer (like the name by the way!) 🙂 I'm so sorry to hear you are going through and have been going through this type of thing for so long. I of course can't and am not going to say I can 100% relate and know exactly how you feel, because everybody is different and everybody's story and struggle is unique, but I can actually say I somewhat feel and have felt very similar things for a while myself. I wrote a lot, so I'll break it up into a couple parts you can skip through/to if you want.
1st being my own personal somewhat relatable story/experience explanation,
2nd being more about the inner workings of it and more details,
3rd being a short little snippet about how these types of thoughts and ideas are seen nowadays,
4th being the basic conclusion and a little bit of hopefully helpful advice/insight.
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1st Part:
I don't necessarily feel like I'm stuck in a dream, but I too contemplate and ponder the possibility that I am either some 'experiment' to an unseen higher force/forces (in this closed system/physical universe, or perhaps a just physically separate universe) for some gain to it/them - like a lab rat to humans - or even worse I'm just a plain and simple psychological and emotional torment subject to some unseen higher force/forces, but for no gain other than maybe just its/their 'entertainment'. Which has led me and resulted in the same behaviors such as attempting to end my own life.
It all started in my very late teen years, maybe ~8-9ish years ago. My whole younger life I was raised with religious beliefs, but around 18 years old or so my brother called me over to his computer one night to show me an article about a supernova - and it immeasurably changed my life and beliefs and I was hooked permanently. That article sparked and helped me discover my interest in things like astronomy, physics, science, cosmology and much more, and in turn philosophy/deep thinking type thoughts, really questioning the nature and essence of not just existence collectively, but especially my own. So this virtually erasing any previous religious beliefs I had, therein opened the door to endless possibilities for how I perceived the meaning, nature, origin and fate of (especially my) existence. I was like an open agent on the market.
So leaving out very specific details to keep it as short and simple as I can, my first 'schizophrenic' or 'delusional' idea/belief was that my mother's then boyfriend would cough 'at' and around me intentionally because I was smoking marijuana. Not too unreasonable or delusional. That then developed into thinking that pretty much any/everybody (especially family/friends) did the same thing. Still not super bad. Then I started noticing a pattern in the timing of the coughs. I noticed people's coughs were very commonly ironically and coincidentally connected with certain things I would do or not do, so that took the delusion a little deeper.
For a while the main delusion was to do with people coughing. It developed a bit deeper of course with a few more layers itself, but this, paired aside with the 'door opening' of my ideas/beliefs about my existence, led to a whole wide range of more thinking. Over a little more time, I started feeling this general same idea with the coughing, about pretty much my collective life and being. I really analyzed and payed attention to things like external events, in general but especially with other people more, and really started noticing the same types of patterns, mainly with irony and coincidental connection. The nature of a lot of things just weren't really 'consistent', or didn't really 'add up', and the way various things occurred or were, and the timing, and predictability, and other various factors like these, helped lead me to the feeling that there had to be something(s) or someone 'higher' as the driving force(s) behind them, because they just wouldn't occur out of complete random unorganized chance/probability.
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2nd Part:
So with my uncertainty and 'open door' and ideas/feelings at that point and philosophy/deep thinking and everything, I discovered something called the "solipsism problem". I already had more or less the same beliefs or ideas that solipsism entails, but discovering there was an 'official' concept about it really helped cement the idea. Very basically and as it is relevant to my point, the solipsism problem says that your own consciousness and existence is all that can be known to exist for you. Or in other words, you can only know for certain that you exist and are the only conscious being, and that your own consciousness is all that exists, and it is impossible to know for certain, let alone experience, any other being's consciousness.
Along with solipsism, there are also other theories, beliefs and ideas, such as panpsychism, pantheism, and mysticism that personally stick out for me. These aren't quite as relevant so I won't go into as much detail, but they do help contribute a little to various thoughts and ideas such as maybe (in accordance/paired with solipsism) I 'am' the universe/all that exists, (consciousness creates reality and existence, and if I'm the only conscious being...) or even more 'mentally ill/delusional' etc. I am or over universal extended time could be 'God' or similar. The last part isn't quite cemented for me and sounds very wonky, especially to pretty much any clinical professional like a psychologist or most therapists, but with some explanation and more details it is actually somewhat feasible at least.
So now with the idea and belief that I am, or very likely could be the only conscious sentient being (perhaps at least in this physical universe/system) it really changes a lot; especially with the paired idea that my existence/things, and (specifically/especially) in essence every other human being I have, do or will encounter and interact with, who appears and is said to be the same as me ('human') is actually not, and there's maybe just... more than meets the eye. It really portrays a certain level of... deceit, in my eyes.
If I had to settle on any one idea about the true nature, meaning and essence of my existence, other than just to simply linearly live then die, it would probably be either -
A) like I just explained, solipsism, mysticism, pantheism, panpsychism etc. If all these external events and types of things are true and occur intentionally purposefully as they appear - and the reason I'm conscious and question and ponder things - could be to mold me into something greater, or 'higher', so in essence for a good reason,
or
B) there could be a far more advanced and powerful, 'higher' (or unseen) driving force(s) or being(s), who created me into this physical world/system as the sort of 'lab rat' type idea I initially mentioned and you can understand/relate to; where they blandly put, emotionally and psychologically torment me through the matter of uncertainty and deceit when it comes to my existence, external events and especially/specifically other (seemingly just like me) 'humans' around me. But I've also come to develop the question as to whether or not even this could be solely for a negative reason (like simply put just for its/their own sick amusement). I've opened up to the idea/possibility that if this is true, maybe similar to A) it or they could be doing it for some (still unknown to me as I haven't quite figured it out yet) good, positive reason, for it/them or even also for me too. Maybe I could be its/their 'lab rat', so it/they can learn more and grow, and possibly even me learn and grow more too - and not inherently negatively just to torment me. Just like my signature quote says, we are/I am made of star stuff, the universe created me, I'm part of the universe; albeit a conscious, sentient, aware and... maybe somewhat intelligent part of the universe, maybe the universe created me and I exist so the universe can discover and learn about and grow itself.
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3rd Part:
Anyways. It's kind of sad and... disappointing, or off putting, I guess, to know that like I briefly mentioned, telling any of these types of things to pretty much any clinical professional like a psychologist or most therapists, will instantly get you labeled and diagnosed as 'mentally ill' and unstable and a crazy looney whack job, who just needs to be put on pills for the rest of your life because you have profound/deep thinking, which instantly makes it worse for you because it doesn't help how you feel about yourself. Just because a good ~95% of clinical professionals are oblivious to, just don't want or aren't interested in, or aren't capable of deep thinking, and things like philosophical questioning of being and existence and the universe, doesn't instantly mean everybody who does/is - let alone who suffers from it - is 'mentally ill' or a virus. In fact, I'm sure plenty of people nowadays, but especially back in way older days, would agree it is or should be the complete opposite; and it is simply inherently human nature to question and think such things. Afterall, we are as far as we currently know, the only conscious, aware, sentient intelligent beings in the entire universe, and that alone is deeply profound and inherently very easily raises some questions and thoughts. So, it's only human, and natural to think and wonder such things, not wrong, or bad.
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4th Part:
So with all this being said, what helps me among numerous other smaller unrelated things, and hopefully maybe you even a little, is mainly just simply the plain and simple matter of uncertainty about anything. You can't be literally, 100% certain of anything. Sure all the signs and data could point to what I feel and think being true, but that doesn't mean it 100% is.
They say "death and taxes are the only thing certain in life", but even that's not true, or 100% true. Sure it's very very (very) unlikely, illogical and improbable, but you could wake up tomorrow and there could be breaking news that the government is no longer charging taxes. Again, very very etc. unlikely, but it COULD, even .01% chance happen. And as for death, well 'death' is just as big of a mystery if not moreso than life, or the universe and existence. Nobody knows for certain 100% what happens when you die, nobody knows what death 'truly is' or entails, other than the idea of no longer -physically- breathing with your heart beating and having brain activity. That's what humans to the extent of our knowledge classify it as. So for all anybody knows, 'death' could be (and sadly honestly more likely than the taxes part...) anything but ceasing to exist and literal complete utter void emptiness of being, and could even be a 'gateway/door' or 'transition point' into a different existence (or in other words you might as well just say you know reincarnation, transformation etc. There are plenty of theories and thoughts on that too of course.)
So just plain and simply knowing that nothing is 100% certain, or the true nature and essence of anything can not be 100% certain, helps me hold onto the idea and hope that things (even when/if they are abysmally dark) can change for the better. Whether it seems 99.9% likely things aren't going to change and get better, or it's 99.9% likely or even 1% likely that I could wake up tomorrow and get the surprise of my life and things could change for the better, that's personally enough for me to keep going. I personally have managed to embrace, and find some comfort in the idea of uncertainty, and that no matter how abysmally black and bad things are or seem to permanently be, there can still be even a .00000000001% chance that tomorrow or in the next 60 seconds there could be a spark of light and change.
Paired with this, I also personally like to apply the good ol' "what doesn't kill you only makes you stronger" saying. While that's not quite 100% true, the moral of it is pretty helpful. If any of my beliefs collectively or marginally are true, then remaining alive and not giving up will likely ultimately only make me stronger; or if not, then at least personally for myself, satisfied and happy knowing I did and am doing my best and not giving up - literally, no matter how abysmally hellish hopeless and horrible things are or will be. That alone, knowing I did and continue to do my best, is and will always be a source of light, good and happiness.
And me collectively giving up, or harming myself, is not going to help anything, it is not going to produce anything good or positive, and it is not going to solve anything, for me personally. (Not to mention also what personally applies to and helps me is the idea that if my ideas and beliefs are true, then even if I did 'end my life', such 'higher' being(s) could just easily recreate me with the snap of a finger every time and 'ending my life' would be futile and pointless) Anybody harming themselves, or me harming myself may be/can be or has been a method of crying for help, or a way to truly express how horrible I/they feel, but it's not the only way, and me harming myself, will, of course, only harm me, read that again - it will only harm me, not help me, it will only harm me. So if you can not collectively give up and continue to do your best no matter what, then harming yourself, again, is not going to help in the long run/bigger picture, and is only going to be bad and cause harm.
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Again, anyways... Hopefully that long wall of text if you read it or any parts of it helped, even simply through knowing that others can relate even a little, and not only sympathize but empathize with you and express and extend care and even a little understanding. There are of course plenty other details, and things to be said about many things I mentioned, but for the sake of not writing a book for you or anyone else to read, I tried to keep it as simple and short as I could while still relevantly explaining things.